Allow non-string error message to be reported to sentry

[the-spectator]

Ref: #907 (comment)

Description

When the def message in the error class is overridden to return a non-string value. Sentry is not able to report the error due to the error NoMethodError: undefined method byteslice' for []:Array`. Ideally, we shouldn't override the message and yet it was done 😓 .

Describe your changes:
Convert non-string error message to string.

[natikgadzhi]

Not related to the core team at Sentry, but the change looks reasonable to me. It's better to send out a longer, slightly awkward error message than to error out.

[codecov]

Codecov Report

Merging #2137 (5617ca3) into master (c4e4797) will increase coverage by 0.00%.
The diff coverage is 100.00%.

❗ Current head 5617ca3 differs from pull request most recent head a5fa2ce. Consider uploading reports for the commit a5fa2ce to get more accurate results

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2137   +/-   ##
=======================================
  Coverage   97.34%   97.34%           
=======================================
  Files          99       99           
  Lines        3687     3688    +1     
=======================================
+ Hits         3589     3590    +1     
  Misses         98       98           

Components	Coverage Δ
sentry-ruby	98.03% <100.00%> (+<0.01%)	⬆️
sentry-rails	94.98% <ø> (ø)
sentry-sidekiq	94.50% <ø> (ø)
sentry-resque	93.65% <ø> (ø)
sentry-delayed_job	94.44% <ø> (ø)
sentry-opentelemetry	100.00% <ø> (ø)

Files	Coverage Δ
...try-ruby/lib/sentry/interfaces/single_exception.rb	100.00% <100.00%> (ø)

[st0012]

Thank you for the fix. Can you also add a changelog entry for it?

[the-spectator]

Thank you for the review! 🙏
@st0012 Added the changelog.